Method of stabilizing slide areas



July 1l, 1950 R RIO'NEAL METHOD 0F STABILIZING SLIDE AREAS Filed Aug. '7, 1948 INVENTOR. AY OWEAL BY Ma ATTONEK I Patented July 11, :1950

UNITED STATES PATENT OFFICE METHOD F STABILIZING SLIDE AREAS Ray R. ONeal, San Francisco, Calif.

Application August 7, 1948, Serial No. 43,080

4 Claims. l

which are diicult to control and which are re' sponsible for a great many destructive slides.

Speaking in geological terms, clay is a hydrous aluminum silicate generally mixed with powdered feldspar, quartz, sand, iron oxides, and certain other minerals. Wet clay in its natural form is plastic and tenacious, but when heated sufficiently, it becomes porous, hard and brittle.

The firing or burning process in connection with clay is called metasomatism. Thus, when wet clay is heated, the first eiect is to decrease its moisture content. The clay then becomes dry, but is not chemically altered; it does not cease to be plastic when cooled and moistened again. If the temperature continues to be raised, however, the chemically combined water is separated and the clay undergoes a molecular change, which change prevents the clay from taking up Water again, except mechanically. Thus, suitably iired clay will retain its porosity but ordinarily will not be restored to a plastic statewhen in contact with water. It might also be noted here that on further heating the clay tends to undergo partial ius-ion, which result is not desired here.

The primary object of this invention is to provide an improved drainage method for slide areas which will afford means for intercepting seepage or other Water contained in the slide area and which will conduct it to a iree outlet, thereby checking the displacement ofthe slide body.

.Another object ci this invention is to provide a drainage system that will be of considerable less cost to install and maintain than other slide preventative structures now commonly used, and one which is highly eiiicient in its operation.

A further object of this invention is to stabilize a slide body and check its downward movement by means of a series of rigid tubular reenforcing members spaced throughout the slide body.

These objects and advantages will be best understood by reference to the detailed description below, together with the accompanying drawing in which:

Fig. 1 is a cross-section of a typical slide areav which has been treated in accordance with my invention;

Fig. 2 is an enlarged sectional view of one of the tubular drainage members located in the slide area; and

Fig. 3 is a similar View showing aportion of The underlying theory of this .invention is based upon the fact that slide areas are mostly composed of clay and clay-like materials, which areas after the introduction of excess water from rainfall, nearby springs or other underground water sources, often become moving bodies.

'I'he density and nature of clay and clay-like materials is such that water seeping into them does not drain o rapidly. The clay material then becomes plastic or semi-fluid with water acting as a lubricating agent often setting the Whole slide mass into motion.

However, by drilling a plurality of laterally inclined holes into or substantially through the slide body or area and then baking or ring the Walls of the holes, a most effective system for draining off excess water is provided. This liring process will form a porous, pottery-like casing similar to drainage tile around each hole. However, it must be noted here that the clay material red in accordance with this method should not lbe fused and thereby have the density of soilpipe, but should be highly porous.

Referring to the drawing, the numeral l indicates a typical slide area comprising a body of Wet clay-like or other similar material which by reasonrof its moisture content Aor its peculiar drainage pattern has become or is apt to become subject to sliding.

In carrying out this invention, a plurality vof laterally inclined holes` 2 are rst drilled with suitable drilling equipment such as an auger from the exposed lateral face of the slide body to points near or at the latters opposite unexposed side.

A suitable pattern which may be used in this method is the drilling of the lateral holes with an approximate 3 per cent rise from their discharge ends to their opposite ends for water drainage from the slide area l. These holes should extend from the exposed face of the slide area l preferably to the inner unexposed side of same area I and should be staggered and distributed in such a way as to afford good coverage of the slide area l.

The next step in carrying out this invention is the firing of the Walls or sides of the drain holes. The liring operation is carried out by the firing apparatus operatively mounted theremeans of suitable heating equipment which bakes the walls of the holes 2 to the desired temperature depending upon the properties of the clay as revealed by a soil analysis of the slide area.

It is to be understood that any suitable type of firing apparatus may be used in applying heat to the Walls of the holes 2, such as an outer pipe 3 havingy a tubular conduit d extending' thereu through and spaced from latters Walls. The

flame, supplied by the gaseous fuel passing through the conduit 4 is supported by suitable air passing through the interior oftheipipefr Electrical or other suitable heating equipment may also be used.

The object of the ring in.tl'lis-prccessisvte-` provide a highly porous, -durable casing 5 around each drainage hole 2 through which the waterfrom the Wet slide areaul may drain. It is to benotedth'at the burning or ring of lthe claylike material at the sides of the vholes is an" important step in this process, for the vaction of' the heat-brings about certain chemical decorou positions andV recombinations which alter' the physical character of the material'and therebyV makesit porous.

The; temperature for ring the drain holes 2l- Will vary according to the type of clay found ini the slide area. By variation in composition, clays are divided into three broad classiications, black, plastic, and sandy, and the temperature ref i quiredfor driving oi the Water in chemical combination in each clay type will be determined by the composition of the particularfclay type. However, for all practical purposesxa temperaturef'rangingfrom 1000 degrees F. toldo() degrees' FL is sufficient to driveoi the Water in chemical combination inallicomrnon clays and'to bake them suitably; 1

Care must be takenrwhen iiring theserdrain holes 2, for too` excessive a temperature, say 1809 degrees F. of 2000 degrees Frorimore; will cause.

th'e iron oxides of the clayto fusel to'oini` a glassy; non-porous substancev called glass. This process is called vitriiication and if employed `here Would-defeat every purpose "o the invention, for instead oiproducing apo-roue casing 5 through. which the excess Water of the' slidefareal could drain, the ring underthese circumstances' v would produce a non-porous;

glassy, imperviouscasing which wouldy` be in'- capable ofV` absorbing Water. y

Water seeping throughithe porous Walls V.i of

each 'casing flows downwardly therethrough and is` drained` from the slide area. In ordinary practice ka roadside drain-ditch is providednat the base of the slide area to convey thev :drained water away.

By means ofthe drainage systemcomprising this invention, the excess Water is continuously drained from the slide body, thereby removing what is commonly recognized as the cause for most slides.

The distribution of the rigid tubular casings throughout the slide body in accordance with the present invention provides a reenforcing structure which holds the slide body-in place.

It is to be understood that this invention may be employed to stabilize lls as well as slide areas.

ZJA- method of stabilizing clayor clay-likesli'debodies having a substantial moisture -content Awhich consists'- in drilling". a plurality of laterally inclined holesthrough the slide body, and ringythesides of the-said holes'to solidify and make porous the'material immediately sur--r rounding the holes.

3. A method ofk stabilizingV clay or clay-likte'v slide bodies having a substantial moistureicon-l tent whichy comprises drilling a plurality of laterally inclined and spaced holes substantiallythrough such aA slide'body, the said holes :having their discharge ends-at'v the exposed 'lateral face- L of the lslide body and the said holes being-dis--` posed with their discharge ends at lower levels than theiropposite ends, and -ring :thefsides -ofV the holes until porous, rigid casings vare formed around'the holes.

4. A method of stabilizing clay or clay-like slide bodies having a substantial moisture content Which comprises forming-anV elongated inclinedhole in such a slide body, the said elon gated hole being arranged to convey liquid col-- lectingxtherein' to a point at an edge yof theisaidfA slide body, and riiring the sides of the said hole' to solidify and make porousthe said sides ci the hole..

RAY R; ONEAL.

REFERENGES CITED The following references are of record inthe le of this patent:

UNITED STATES PATENTS Name Date Dresser .July-9, 1946 Number 

